Siemens SINAMICS G220 Operating Instructions Manual page 510

Functions
14.10 Closed-loop drive control
Description of function
Only for induction motors
1)
Choice of control mode
2)
Settings required
3)
Figure 14-116 Simplified function diagram for speed control with a speed controller
The converter uses the motor model to calculate the following closed-loop control signals
from the measured phase currents and the output voltage:
• Current component I
• Current component I
• Speed actual value for encoderless speed control
The setpoint of the current component I
For speeds above the rated speed, the converter reduces the flux setpoint using the field
weakening characteristic.
At an increase of the speed setpoint, the speed controller responds with a higher setpoint
of the current component I
higher torque setpoint depends on the motor type:
• For induction motors, the closed-loop control adds a higher slip frequency to the output
frequency. The higher output frequency also results in a higher slip in the motor, which is
proportional to the accelerating torque.
• For synchronous motors, the closed-loop control increases the load angle instead of the slip.
508
d
q
(flux setpoint) is obtained from the motor data.
d
(torque setpoint). How the closed-loop control responds to the
q
Operating Instructions, 04/2024, FW V6.2, A5E51781573B AB
SINAMICS G220 converter